Charging devices with so-called variable turbine geometries are becoming increasingly widespread in order to be able to better adapt the power output and the response characteristics to different operating conditions such as for example load changes. To this end, the variable turbine geometry has adjustable and non-rotating guide vanes in the turbine inlet or in a housing. For thermodynamic efficiency, a regulating characteristic and required radial installation space, the shape of the guide vane profile is decisive, while the shape of the guide vane as a rule is described via the so-called profile centre line (curvature line) which runs between the centre point of the head radius and the centre point of the end radius of the guide vane. The profile centre line is determined by placing circles which are tangential to the top and bottom within the profile of the guide vane, wherein the centre points of these circles describe the profile centre line.
From U.S. Pat. No. 6,709,232 B1 a generic charging device with rotatably mounted guide vanes for a variable turbine geometry is known. There, the known guide vanes have a continuous profile centre line.